Concrete mixer



H. F. WILMS Nov. 15, 1932.

CONCRETE MIXER Filed Jan. 28, 2 Sheets-Sheet 1 INVENTOR. flan 3r (7, Zfz'fms Nov. 15, 1932. w|LMs 1;888,100

' CONCRETE MIXER Filed Jan. 28, 1931 2 Sheets-Sheet 2 INVENTOR. flea/y .9. 7/277/15 Patented Nov. 15, 1932 HENRY FILMS, F CLEVELAND, OHIO, A

PORATION, OF BAY CITY, MICH ssrenon'ro mnus'ramn enowmiorsr con- IGAN, A CORPORATION OF OHIO I 'conoanrn MIXER,

Application med January 28,1931.

This invention relates to mixing drums used for mixing concrete and the like, and,

more particularly, to the interior'me'chanism of such drums comprising blades, flights, or pick-up buckets. 1, a

A more ready comprehensionof therinvention may be had from a consideration of the difficulties encountered in constructing and operating concrete mixers' equipped with the 0 interior mechanisms now employed in the art.

or spoon These mixers are of three general types; first, those that revolve only in one direction andhavea mixing blade arrangement requiring the insertion of a discharge chute to discharge the contents when mixing has been completed; second, those in which it is necessary, in order to discharge the vessel, to tip the whole mixing drum at one end in order to permit the contentsto flow out by gravity; and third, those in which the drum is made conical at the discharge end and the mixing blades extend along the inside of this cone to discharge the contents. It may be noted that, in this third type, the

discharge arrangement is limited to one in which the angle of the sides of the cone with the horizontal is not greater than that at which concrete will flow by gravity, otherwise the mechanism will not discharge its contentsfast enough to be commerciallypractical;

It will be appreciated that each of the three types of. mixers defined above are subject to certain disadvantages in the operation of discharging'the mixer, as, for instance, the necessity for the insertion of a separate element, a discharge chute, into the drum, power necessary to tip the entire mixer where this method of unloading is used, or the limi- 0 tations to the speed of discharge attainable tioned. Where the vessel'is so mounted,

with a conical discharge'endL In addition,

it is often desired to mount aconcrete'mixer on a motor truck and thishas been done with each of the three types of mixers above men- "limit the gross load the Serial No. 511,828.

may berevolved either by its own power plant l or by a properly designed mechanism driven by the engine of the motor truck. l/Vhen the unit is thus made mobile however, further mechanical difficulties and limitations are encountered. For example, it is necessary kept down so above all that the weight of the mixer be as not to over-load the truck or limit its useful load, i. e. mixed concrete,

of thevarious States that maybe carried on the highways. Another limitation" on designis imposed by the necessity for locating the center of gravity of the mixer since the road laws truckbecomes unstable and,also, the various a definite percentageof the total load which may be carried on the rear axle. A longer mixer would therefore require a truck with a longer wheel base in order to bring the cenahead of V.

the rear wheels of the truck, otherwise the State laws are again encountered, which fix ter of gravityforward ofthe rear wheels, but motor trucks. with long wheel'bases do not have the maneuverability of thosewith shortor wheel bases and are. more expensive.

Where mixed concrete is beingdeliveredrto' the site of an office building located in the business section of a large city} extremely little space is truck into position to unload, and lengthening the wheel base to stabilize a truck is, practically, not an available expedient. Another difliculty arises whenthe truck mustbe discharged from ground which is not level; If

the truck is on a grade with the rear end higher than the too slowly and will take up time allocatedto following trucks in the closely timed sched w front end amixer of any I one of thefabove three typeswill discharge available for maneuvering a r so f ule which is necessarily established for the l delivery of materials in modern city con- 'struction. v If the grade issulficientlysteep, say a grade of 15 per cent, the'mixer is pre vented from discharging its entire load,

sometimes leaving almost one-half of the load remaining in the vessel.

Further mechanical diiliculties encountered when a mixing drum is mounted on a truck follow from the custom of closing up both the charging and discharging openings of the mixer with a removable door or gate to prevent the drum from spilling its contents while mixing. This discharge door or gate causes the operating mechanism to increase in complexity when the discharge chute method of emptying the drum is used and also adds In the type of quired similar to those used on the dump bodies of trucks, which also adds considerably to the expense and weight and complicates the mixer.

Having in inind'the above set forth disadvantages inherent in the various types of mixers in use at the present time, it is an object of my invention to provide an entirely new type of mixerdrum which is more efficient in its operation under varying conditions, due to its simplicity and its freedom from moving parts. Another objecu of the invention is to provide a. mixer which is more economical to construct and operate'due to its lightweight and low Still another object of the invention is to provide a mixer which may be discharged quickly on any grade likely to beencountered in actual use. A further object of'my invention is to provide an entirely new type of mixing blade for mixing drums, the new type of blade avoidingthe necessity for a discharge chute, tilting of the entire drum to discharge, or for a low-angle cone at the discharge end of the drun To the accomplishment of the foregoing and related ends, said invention, then, con

sists of the means hereinafter fullydescribed and particularly pointedout in the claims; the annexed drawings and the following description setting forth in detail certain mechanism embodying the invention, such disclosed means constituting, however, but oneof various mechanical forms in which the principle of the invention maybe used.

In said annexed drawings Fig. 1 is a longitudinal vertical section taken along. the center line of the mixer; Fig. 2 is an end elevation of the discharge end of the mixer drum; Fig. 3 is a transverse section taken along the line 33 ofFig. Fig; 4 is a view in perspective of terior mechanism of a drum of the drum cut away; ant elevation of the mixer truckf Concrete mixers, when truck, are usually arranged to rotate in either direction, andit is the common practice to reverse the direction of rotation while Fig. 5 is a side mounted on a motor mounted on a considerably to the weight." mixer in which the'entire drum is tilted up to discharge, a hoist is re-:-

cost of manufacture.

discharge head of the drum a part of the illwith a portion new and improved"mechanism comprised by the manner in which mix-v the invention and ing and discharge is accomplished thereby. In Fig. 1 a mixer drum 6 is of the conventional type'and has attached to its inner. sur face one or more flights or blades 7. Toward the rear of the drum is found the blade 8 having its counterpart 9 in the half ofthe drum not shown, these blades having the double function of both mixing and discharging. .7 A balile 11 is attached to blades 8 and 9 and lies in a plane defined'by the center line and a diameter of the drum. The opening 13 cooperates with a flared discharge or drip ring 14, which is usually used in combination with a door (not shown). The front head 15 of the drum is usually not provided with apertures, being left blind. The manner of attaching the flightsi, which may be termed auxiliary blades, since they assist the function of-the. blades 8 and 9, may be seen in Fig. 3.

Referring to Figs.2 and l of the drawings, the blade arrangement characterizing my invention may be clearly seen therein. Blades 8 and 9 are locatec near the discharge end of the drum, being, in fact, attached to the at the ends 16 and 17 and being also attached to the inner wall of the drum 19. Each blade is inclined at an angle to the center line of the drum, this angle being, in

the preferred form, approximately but it will be appreciated that the angle of the blades may be modified considerably to meet various operating requirements. The blades are also placed at an angle to each other, one sloping downwardly toward the rear of the drum and the other sloping downwardly toward the front of the drum when the apparatus is in the position shown in Fig. 4', their respective planes thus forming vertical angles with each other, since the blades are in diametrically opposite sides of the drum. The attachment of the blades to the wall of the drum may be by I means of angle irons 12. The blades contact with. the rear head of the -drum on lines a 3 roximatel tan 'ent to the l y e discharge opening 13. I

Closely cooperating with the two blades 8 and 9 is the baffle 11, aforementioned, which is placed perpendicularly between the two blades, to the inner edges of both of which it is fastened by electric welding or other suitable means. It completely spans the space between the blades at the point of at their outer edges 18 and Ian ' .rection. At there'ar,

ihg 22; hrou'gh which the "mixeris is revolved in the the opposite direction 7 sesame I re "coea eebjnt u e aisehar'ge heads a when the blades fie 11, sp nning the's'p'ace between the blades at their rear 'ends' and :connectin'gthe' blades,

is productive othighly-important results,

jas will appear atlen'gthfhereinafter.

In Fig; 5 may be seenvariousiadjunctsylin addition to the 'trucli'shownyto the operation of the mixer, such as the charging fopenicharged and which is'closed before the drum isre-' volved5 and driving means drum to rotate through the driving gear'24. The rear end of the drum is rotatably mounted on the roller track 25. Water is carried in the tank 26 and is supplied to the concrete mix through the water bells 27.

The manner of operating the mixing drum is as follows: The drum is all the materials necessary for the formation of concrete or for whatever product it may be desired to mix in the app aratus. This may be done through thechargi'ng opening22 or through the discharging opening 13,-in the former case the drum beingrevolved until the opening 22 is on top, the material allowed to flow in, the doors closed and the drum started revolving. is arranged so that the vessel can be revolved in either direction as desired. lVhen it is desired merely to mix countereclockwise when viewed from the discharge end. The materlal in the drum Wlll the blades 8 and '9 and also the auxiliary blades 7 slicing through the mass and mixdesired to reverse the ing it. hen it is movement or the aggregate the operator reversesthe direction of 2 in Fig, '2 ofthedrawings and: the" material is pushed in I toward the discharge end of the drum, the the material asbefore, but in the opposite dien bafiie 11, forming a pocket withthe blade 9, carries some of the material toward the top of the drum, discharge through-the opening 13 being prevented by closed during mixing.

dropped twice in each revolution by blades 8 and 9 in combination with the baflle 11, which results in a very thorough mixing of the ingredients and insures falls down, the

23 causing the blade andreturningi'to' any movement of first charged with in t r e;

ting the truck on T .moved outof the way in-a very1sho rt' time. The'drive for: the drum v Qbe dis harsed v oug the materials the drum gid b higher than its-front end; It direction of the arrows 1 v on Fig. 2 of the drawings,this direction being rotation of the drum unit i ,v n p d to that indic'ated'by arrows blades slicing through I I japparatus of] this nature; d of the drumlthe "st temen d Other modes of applying,thejprinciple ot a door keptnormally 1 I As this pocketcon-, v tinues to revolve, it passes the upper limit of W QPQQ i db mp ysd J n i fi l a s the ,-0ne"eXpla1ned, change being'madeas 5 regards the mechanism ,vided the meansstate ing claims; or I 'thequiv apparent that the material is picked up and "means be employed.

that there will bit the mixer, the door the discharge opening .13fis opened and the drum is "revolved in the direction of the arrow 2, the blades'S and 9 picking-up the material and; raising it antiithe angle of the b1ade with the horizon- Ztal becomes greaterf thans'theangle of re- F whereupon the) "latter poster thniatefiahr I I I and out throughj'the I thejb'ottomfof'the drum since the baffle:l' lefiectively prevents of the material flowing ever edge of the 'ening.

r idischarge opening-*Therej is no possibility so i .rial iexcept outwardly -'1;1 u the I chatgg I 7 As the disoharging opm I ceedsit; will :be'jseen that a11 0themateha1 fintheid'fim will be arcade-(s am;asses p ck or dlbri a st-a di-befi e y theiauziilia'ry; blade andflthe 'bladessfand 9}themselves 1 and; once these terial can s n q k i take but one course,- cha se cramps sequence the quicklyi emptied "of its contents, thusipermitwhich itfis [carried to be Since the "concrete is raised by'theipoekets u w rd y f'a i ndrum is very completelyand above :thetopmm oi theidrumttheidrumcan itsrea'r end rests isfojnlyl fne'oe's saryithat the concrete be raised 3 beneath to: t m l o th ough th Qp nihaflb, ,T'N'o, a cesso y P r a i de ft V s 1 di ha g t rum; uc be pushed toward the blind head of the mixer,

discha aefchute I or a low-angle cone at, the discharge end.-

wast wise-a t Y rangement or combination of blades hasbeen used heretofore 'infconcrete ihixersor other Y bl de, corh struction is considered; t' f be entirely new in r in its vbroadest aspects,

' i mobile I 'hetherus 'edflin connotion with y alentof "stated "I thereii ore particu tinctlv claim as'I vlinventionpe j 1, 7 v gthelcoe ne two mixlngblades', fastened-to sa did'nu a d.

ens ofits'head's, andfaibaflle'fastenedto said" :the art and it is 'dsire l to claim the Sam m ii a nf t? or-i a v head to form drum metrically disposed fastened to said head, said blades, bafile and 1, .tolform pockets-to eject .nation of means .for,

posed and oppositely.

" .to the shell head interconnected .rection of 'itsrotation head and-extending therefrom on ;thedrum s median plane between said blades and fastened to thesame, said blades lbein g .0pp0-' .sitely inclined with respect to said median plane, and cooperating with said bafiie and pockets .to collect and eject the mixed concrete from the drum.

In a mixing. drum, the combinationof two diametrically opposed and oppositelyinand to one of itsheads, of albaflieldiabetween" said blades, and head interconnected the mixed contents of the drum. n a 3. In a revolvablemixing drum, the combi- .rev0lving said drain in tached to the wall of I ha e forming clined blades attachedto the shell .of said of the drum opening; 3 I a V p a Signed 'byme, this 21st day of January, 7

ing said'driim'in,

the head of {said drum, two diametrically opposed and oppositely inclined I blades ati said drum andjoined through abafile perpendicularly disposed between them, said blades being attachedatone either directiom'an opening end to the head of said drum approximately tan ent to saidopeningand said blades and pockets to agitate the contents and to eject the same from sald EHENRY F; WILMS.

eitherdirectiomaclosable aperture intone of V the heads of saiddrum, two diametrically op inclined blades attached of saiddrumancl' tosaid headat points, approximately tangentialt'o said aperture, of a ba'flle diametrically disposed be tween said blades vand iastenedto'the blades and to's'aid head, said shell, blades, bafiie and tate the contents of the idrnm during, one di- Jhrough said apertureduring reverserotation.

.4. In a drum capable having an opening-in the drumhead, the com- 5. I two mixing blades two mixing blades,

placed perpendicular to form pockets to agi and to e'ject the same I of beingjrevolvedand V bmation of two diametrically opposed blades attached alon r theirinner-edges to op osite faces of a 1121 .e yf f I tween them, one of saidblaclesslopingdown- I wardly toward therear ofsaiddrum and the other sloping downwardly toward the front of said drum when saidhafiiejis iinayertieal position, and the rearendsof saidbladesbe- I fing attached to said drum head approximately on atangenttosaid opening. n a; mixing drum, the comb nation of in said drum,said,blades being diametrically opposed, attached to opedges and, attached to oppositefljfaces" of a baifie placed perpendicularly between them posite sides of the drum wall-atltheir' outer I at their inner edges, and therrear ends Ofsaid; p p blades being approximately tangent to fan rear head ofsaiddrum.

opening in the p v n a m1x1ng, drum,,the comb nation of ing attached to the wall of saididrum andito being oppositely-inclined with respect to the two diametrically clined blades attached-tothe wall and a hafi le, said blades beopposite facestofsaid baffle, and said blades center line of said drum, forming poc kets opposediand oppositely ina 7 of said;

drum and to abafiie perpendicularly disposed I between them, said'blades andbafile forming pockets to eject vthe contents of the dr .8. Ina mixing drum capableofrbeingerev,olve.d, thecombinationof meansfor revolv 

